Met Éireann has warned that some St Patrick's Day parades will take place in temperatures of just 1C, a startling drop of almost 10C from the milder conditions earlier this week.

Overnight temperatures in some areas will plummet to as low as -5C this weekend, with very heavy frosts predicted.

North Leinster and Ulster are expected to witness showers of snow and sleet, some of which may be quite heavy.

The snow showers follow torrential rainfall on Wednesday, which caused flooding in Kilkenny, Cork and Dublin.

Major flood barriers remain in place across Cork with rivers including the Blackwater, Funcheon and Lee threatening to break their banks.

However, icy conditions will be the dominant feature of the weather for the next week.

"It will be a very cold day almost everywhere, so the advice for all parade-goers and marchers is to wrap up well," a Met Éireann spokesperson said.

"The winds will be from the east, so it will seem even colder than it actually is."

Cloudy and misty with showery rain in the east and north this morning which will clear later to scattered showers with some sunny spells developing. Showers turning heavy with the risk of the odd thundery downpour in the southwest. Top temperatures of 7 to 11 degrees.

While afternoon temperatures will reach between 3C and 5C today, they will fall further overnight and Dublin is likely to witness bracing temperatures of between 1C and 3C for its St Patrick's Day parade.

Met Éireann predicted that it will be slightly warmer in Connacht and parts of south west Munster, though temperatures won't rise above 5C anywhere.

Temperatures are set to plunge to 0C over the next few days

The Scandinavian front will dictate Irish weather for the next few days, with icy conditions expected to last until next Wednesday.

Sunday and Monday mornings will witness a particularly heavy frost and gardaí and the Road Safety Authority (RSA) urged motorists to drive with care given the possibility of black ice, particularly on roads which are still water-logged from the rainfall on Wednesday.

Irish Water Safety and the Irish Coast Guard urged people out walking in coastal areas for the St Patrick's weekend to exercise extreme care, given the blustery conditions likely.

The Department of Housing said that local authorities would salt roads where required over the weekend, adding there were ample supplies of salt in stock.

It also said the severe weather assessment team would monitor the situation over the coming days.